ExpandColumns

Expand columns that contain lists into multiple rows.

ExpandColumns is a Step that takes a list of columns and expands them into multiple rows. The new rows will have the same data as the original row, except for the expanded column, which will contain a single item from the original list.

Attributes

• columns: A dictionary that maps the column to be expanded to the new column name or a list of columns to be expanded. If a list is provided, the new column name will be the same as the column name.

Input & Output Columns

graph TD
    subgraph Dataset
        subgraph Columns
            ICOL0[dynamic]
        end
        subgraph New columns
            OCOL0[dynamic]
        end
    end

    subgraph ExpandColumns
        StepInput[Input Columns: dynamic]
        StepOutput[Output Columns: dynamic]
    end

    ICOL0 --> StepInput
    StepOutput --> OCOL0
    StepInput --> StepOutput

Inputs

• dynamic (determined by columns attribute): The columns to be expanded into multiple rows.

Outputs

• dynamic (determined by columns attribute): The expanded columns.

Examples

Expand the selected columns into multiple rows

from distilabel.steps import ExpandColumns

expand_columns = ExpandColumns(
    columns=["generation"],
)
expand_columns.load()

result = next(
    expand_columns.process(
        [
            {
                "instruction": "instruction 1",
                "generation": ["generation 1", "generation 2"]}
        ],
    )
)
# >>> result
# [{'instruction': 'instruction 1', 'generation': 'generation 1'}, {'instruction': 'instruction 1', 'generation': 'generation 2'}]